error on the logs when editing a blog post

2017-12-01 15:55:40,474 [http://mouhb-bu401lg:8080/xwiki/bin/jsx/Blog/ManageCategories?language=en&docVersion=1.1&mode=select] WARN  c.x.x.w.s.JsExtension          - Error at line 400, column 42: invalid property id. Caused by: [    var toggler = new Element("a", {class : "subcat-toggle-link"}).update(downIcon);] 
2017-12-01 15:55:40,475 [http://mouhb-bu401lg:8080/xwiki/bin/jsx/Blog/ManageCategories?language=en&docVersion=1.1&mode=select] ERROR c.x.x.w.s.JsExtension          - Runtime error minimizing JSX object: Compilation produced 1 syntax errors. 
2017-12-01 15:55:40,475 [http://mouhb-bu401lg:8080/xwiki/bin/jsx/Blog/ManageCategories?language=en&docVersion=1.1&mode=select] WARN  c.x.x.w.s.JsExtension          - Failed to compress JS extension: null